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Don't Go To Bed Angry: The Science-Backed Reason To Resolve Arguments Before You Sleep

We've all heard the age-old advice: “Never go to bed angry," but we tend to prioritize a good night's sleep over a dreaded back-and-forth discussion of who's right or who's wrong. Now, a team of researchers suggest sacrificing our sleep to deal with our dilemma, may prevent bad memories from being stored in the brain.

“We would suggest to first resolve argument before going to bed; don’t sleep on your anger" Yunzhe Liu, lead author from the Beijing Normal University, and a student in neuroscience at University College London, told The Guardian.

In the study, published in Nature Communications, researchers found participants had a difficult time suppressing memories after sleep. Brain scans revealed memories were likely being stored and processed in the brain, moving from short- to longer-term network. Typically, sleep helps people process information from the day and store it in their memory.

While we’re asleep, the brain is busy forming new memories, consolidating older ones, and linking more recent with earlier memories, during both REM and non-REM sleep. For example, sleep before learning helps the brain prepare for the initial formation of memories. Therefore, sleep is essential to help save and store new information into the brain, so we're less likely to forget.

However, this could be detrimental when it comes to bad memories — like an argument before bed. Especially since memories of negative or traumatic events often last longer than those of positive or neutral experiences.

To determine whether it's better or worse to suppress memories before or after sleep, Liu and her colleagues used a technique known as "think/no-think" on 73 male students in England, while scanning their brain activity. The participants looked at 26 neutral photos of people's faces, meaning the photos were not associated with either positive or negative emotions. However, each of the neutral photos was paired with an upsetting image, such as a photo of corpses, crying children, or injured people.

Scientists find "sleeping it off" after a fight may store bad memories in the brain for longer periods of time.Photo courtesy of Pixabay, Public Domain

The participants were trained to associate each face with an upsetting image. Afterwards, the researchers showed participants some of the photos again, and asked them to suppress, or forget, their memories of the associated unsettling images. Here, the students were nine percent less likely to remember the upsetting images compared with other, baseline images the researchers showed the participants to test their memory performance.

The experiment was repeated the next day, after the participants got a good night's sleep. This time, the students had more trouble forgetting the upsetting images that were paired with the faces. They were just three percent less likely to recall the upsetting images compared with the other, baseline images shown earlier on.

This suggests sleep could make it harder for us to forget bad memories.

The brain scans also revealed the hippocampus — the brain's memory center — was most active when the participants were asked to suppress memories before they slept. However, on day two of the experiment, after they got a good night's sleep, other brain regions became activated when they tried to suppress bad memories.

Liu believes understanding how the brain suppresses memories before and after sleep could potentially aid post-traumatic stress disorder treatments. However, she cautions the findings are not immediately applicable to those who suffer from the condition. Expecting people who have undergone a traumatic experience to suppress the memory on the same day is ludicrous, but it could help with the design of future treatment.

"For example, sleep deprivation immediately after traumatic experiences may prevent traumatic memories from being consolidated... and thus provide the opportunity to block the formation of traumatic memories," wrote the authors.

Ideally, we would all like to solve our woes before bedtime, but realistically, it's not always feasible.

A simple and mature agreement to "talk about it in the morning" could help ease the tension between partners, and the brain.